Automatic-feed nailing machine



March 5, 1957 s. SCHWARTZ 2,783,468

AUTOMATICFEED MAILING MACHINE 3 Sheets-Sheet 1 Filed Jan. 13, 1956 I IN VEN TOR. 'SAMuEL ScHwAR'rz BY add/1 RTTORIVE Y March 5, 1957 s. SCHWARTZ 2,783,468

AUTOMATICFEED NAILING MACHINE Filed Jan. 15, 1956 86 3, :1 88 i .z 22 J l 3 47a 54 8- 52 64 94-7; 1

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SAMUEL ScHmnmz ATTORNEY March 5, 1957 s. SCHWARTZ 2,783,468

AUTOMATIC-FEED NAILING MACHINE Filed Jan. l3 1956 3 Sheets-Sheet 5 INVEIU'ILOR :BYSAMUE SCHWARTZ ATTORNEY United States Patent AUTOMATIC-FEED NAILING MACHINE Samuel Schwartz, Philadelphia, Pa.

Application January 13, 1956, Serial No. 559,021 15 Claims. (Cl. 1-46) The present invention relates generally to nailing machines and it relates more particularly to magazine-type hammers which automatically feed nails or the like to a reciprocable ram or plunger so that a single manual actuation of the ram is all that is needed to drive home each nail.

An object of the present invention is to provide a new and improved magazine hammer which is simple and inexpensive to manufacture and, at the same time, efficient and dependable in operation. Another object of this invention is to provide a magazine hammer which will handle different-size nails (including variations in head diameter as well as shank length and diameter) interchangeably and without the need for involved and time-consuming change-overs to accommodate such different-size nails. A further object of this invention is to provide a magaz'ine' hammer having novel slide mechanism for transferring individual nails from the magazine to the ram or plunger. Still another object of the present invention is to provide a magazine hammer having novel mechanism, of the cooperating chuck-jaw type, for receiving individual nails from the slide and for releasably holding them in position to be driven home upon actuation of the ram or plunger.

Other objects and advantages of the present invention are apparent in the following detailed description, appended claims and accompanying drawings.

For the purpose of illustrating the invention, there is shown in the accompanying drawings a form thereof which is presently preferred and which has been found in practice to give satisfactory results; it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown, and that various changes and modifications can be made without departing from the spirit or essential attributes of this invention.

Referring to the accompanying drawings in which like reference characters indicate like parts throughout:

Figure 1 is a side elevational view of a magazine hammer or nailing machine forming one embodiment of the. present invention.

Figure 2 is a bottom plan view of the embodiment of Fig. 1.

Figure 3 is an enlarged exploded perspective view of the embodiment of Fig. 1.

Figure 4 is a vertical cross-sectional view taken generally along the line 4-4 of Fig. 1, with parts broken away.

Figure 5 is a vertical cross-sectional view taken generally along the line 5-5 of Fig. 4.

Figure 6 is a view like that of Fig. 4 but showing the ram in depressed slide-shifting position.

Fgure 7 is an enlarged front elevational view of the slide and ram mechanism in the position of Fig. 6.

Figure 8 is a view like'that of Fig. 7 but showing the slide and ram mechanism in the process of returning to the position of Fig. 4. p

ice

Figure 9 is a horizontal cross-sectional view taken generally along the line 9-9 of Fig. 7.

Figure 10 is a horizontal cross-sectional view taken generally along the line 10-10 of Fig. 8.

Figure 11 is a view like those of Figs. 7 and 8, but with parts broken away and with the slide shown as fully returned to the position of Fig. 4.

Figure 12 is a horizontal cross-sectional view taken generally along the line 12-12 of Fig. 11.

Figure 13 is a view like that of Fig. 11 but showing the ram in depressed nail-driving slide-shifting position.

Figure 14 is a cross-sectional view of the slide, taken generally along the line 14-14 of Fig. 16.

Figure 15 is a cross-sectional view, taken generally along the line 15-15 of Fig. 18.

Figure 16 is an elevational view of the slide taken generally along the line 16-16 of Fig. 3.

Figure 17 is a cross-sectional view taken generally along the line 17-17 of Fig. 16.

Figure 18 is a cross-sectional view taken generally along the line 18-18 of Fig. 2, showing the follower spring mechanism for the nail magazine.

Figure 19 is a cross-sectional view through the nail magazine taken generally along the line 19-19 of Fig. 1.

The embodiment shown generally in Figs. l-3 includes an upright elongated main body or block 30 which may be generally rectangular in cross-sectional configuration and which may be cast or otherwise integrally formed of metal or the like. The other main components include an operating ram or plunger 32 vertically reciprocably mounted within the block 30; an elongated nail magazine 34 connected to the block 30 and extending generally horizontally and rearwardly therefrom; a handle 36 firmly connected to the upper end of the block and also to a rearwardly disposed portion of the magazine; a slide 38 constructed and arranged to reciprocate transversely of the block and adapted to transfer individual nails or the like from the delivery end of the magazine to the interior of the block; and a pair of cooperating jaw members and 42 pivotally mounted within the block and constructed and arranged to receive the individual nails from the slide and releasably to hold them in vertical alignment with the ram, so that each operation of the ram drives home the nail held by the jaw members, the slide being connected to the ram so that operation of the ram causes actuation of the slide to bring successive nails into position within the jaw members.

As best shown in Figs. 3 and 5, the block 30 is provided with a cylindrical bore 44 extending downward from the top wall 46 thereof and leading to a lowermost chamber 48 of enlarged generally elliptical cross-sectional configuration which extends upward from the bottom wall 50 of the block as shown in Figs. 2 and 5.

The front wall 52 of the block 30 is provided with an elongated vertical recess or groove 54 which is substantially co-extensive with the bore 44, with which it communicates through an elongated vertical slot 56; the. ends of the slot 56 terminating somewhat short of the ends of the groove 54. i

A transverse kerf or notch 58 is formed in the front wall 52; the lower end of the groove 54 leading'intosaid the bottom wall of the kerf 58 and extends later-tallyin ward from one sidewall 62 of the block 30, terminating short of the other side wall.

The jaw members and 42 (which preferably are integrally formed of resilient steel or the like) are pivotally mounted on pins 66 and 68 which are set into holes 70 and 72 extending horizontally and rearwardly from the block front Wall 52 on opposite sides of the groove 54. The upper ends of the jaw members 40 and 42 are bent to provide sleeve portions 74 and 76 through which the pins 66 and 68 extend; the free ends of the sleeve portions being bent and stressed laterally outwardly to form leaf spring shoulders and 77, best shown in Fig. 3, which bear against the sides of the elliptical chamber 48, as shown in Fig. 11, and urge the main suspended portions of the jaw members together, within the elliptical chamber and below the ram position. The facing surfaces 78 and 80 of the jaw members are concavely arcuate and have a slight downward and inward taper, so that the jaw members touch only along their front and back edges and have a downwardly diminishing annular clearance therebetween.

The front edges of the jaw members are provided with nail-receiving fingers 82 and 84, both of which extend transversely in the same direction; i. e., toward the side wall 62. The fingers function to remove nails from the slide 38 and successively to position them intermediate the jaw surfaces 78 and 80, as will be described.

The ram or plunger 32 is cylindrical and fits slidably within the bore 44 but protrudes upward beyond the top wall 46 of the block 30 and has a knob 86 mounted on its upper end. A helical compression spring 88 is disposed about the protruding portion of the ram, with its ends seated against the knob 86 and the top wall 46 respectively; the spring serving normally to maintain the ram in the elevated position shown in Figs. 4 and 5.

The ram 32 is provided with a reduced-diameter lower portion 90 terminating in a beveled-edge fiat circular nail striking face 92. In the uppermost position of the ram, the face 92 is located somewhat above the concave surfaces of the jaw members 40 and 42. When the ram is forceddownward (against the pressure of the spring 88) by manual pressure applied to the knob 86, the reduceddiameter portion 90 moves downward between the jaw members to the position shown in Figs. 7 and 9, wherein the face 92 is below the lower ends of the jaw members, and wherein the annular lower edge of the main cylindrical portion of the ram has moved between the jaw faces 78 and 80 and has spread the jaw members apart somewhat to nail-releasing position.

Slidably mounted within the vertical groove 54 is a cam member 94 having an apertured boss 96 which extends rearward through the slot 56 and into a correspondingly shaped socket formed in the main cylindrical portion of the ram 32. A screw-threaded bolt 98 (see Figs. 3 and 4) passes through the apertured boss 96 and connects the cam member 94 to the ram 32 for vertical reciprocation therewith.

The cam member 94 is provided with a lowermost inclin'ed or diagonal camming edge 100 which, in the lowermostposition of the ram 32, extends downward into the area of the kerf 58 and fits within a cam-receiving notch 102 formed in the front wall 104 of the slide 38.

The notch 102 has an inclined cam-follower surface 106 which is contacted by the camming edge 100 during downward'movement of the ram 32 and the cam member 94 so as to impart a horizontal transverse movement to the slide 38 from the righthand position of Fig. 4 toward the lefthand position of Fig. 6.

The front wall 104 of the slide 38 is also provided with a relatively narrow horizontal groove 108 which is disposed slightly below the top wall 110 of the slide and which leads into thenotch 102, as best 'shown in Fig. 3.

The back wall 112 of the slide 38 (see Figs. 14, 16 and 17) is provided with a relatively narrow horizontal groove 114 located at the same distance below the top wall 110 as the groove 108. However, the groove 114 is longer than the groove 108 and extends therebeyond, terminating nearer one of the side walls 116 of the slide. Throughout their overlapped portions, the grooves 108 and 114 are in communication so as to form a narrow opening extending through the slide 38 as best shown in Fig. 17.

At a level somewhat below that of the groove 114, the back wall 112 of the slide is provided with a wider but shallower groove or kerf 118 which extends horizontally across the entire length of the slide, as shown in Figs. 14 and 16.

A vertical groove or notch 120 is also formed on the back wall 112 of the slide, extending upward from the bottom wall 122 of the slide, across the horizontal groove 118, and leading to the groove 114 at a point within the communicating zone of the grooves 114 and 108, as best shown in Figs. 14, 16 and 17.

The nail magazine 34 is of novel construction enabling it to accommodate nails of different size heads and different shank diameter and length and may be integrally formed from a length of metal channel, more or less T-shaped in cross-section, with an upper enclosed portion from which depend a pair of elongated laterally spaced flanges 124 and 126; the latter being somewhat wider than the former. As shown in Figs. 2 and 19, the uppermost enclosed horizontal portion of the channel provides a pair of elongated laterally spaced supporting shoulders 128 for the heads H of the nails N, with the stems or shanks S of the nails extending downward between and beyond the flanges 124 and 126. The vertical clearance within the uppermost enclosed horizontal portion of the channel is several times the thickness of the nail heads. Thus, while in theory the nails within the magazine 34 would have their shanks parallel and their heads in coplanar rim-touching relationship as shown in Figs. 1 and 2, in actual practice I have found that there is a tendency for the nail heads to overlap one another, as shown in Fig. 18, with the rim edges contacting the shanks of the adjoining overlying nails and with the shanks inclined from parallel relationship with each other. The extra vertical clearance within the uppermost enclosed portion of the magazine channel is sufficient to permit the successive inclined overlapping of several nail heads. This novel feature makes it unnecessary for the heads of all the nails to be identical and permits the device to be loaded with an assortment of different nails.

The forward end of the magazine 34 is secured to the left side wall 62 of the block 30 so that the uppermost horizontal enclosed portion of the magazine channel is at the same level as the groove 114 in the slide 38, so that the head of the first nail in the magazine can protrude partway into the groove 114 when urged forwardly, as will be hereinafter described.

The adjoining side of the uppermost horizontal enclosed portion of the magazine channel is cut away at its front end, as shown in Figs. 3, 4, 11 and 13, to permit the first nail to be shifted laterally out of the magazine channel under the action of the slide, as will be hereinafter described.

The forward end of the magazine channel is attached to the left side wall 62 of the block 30 by a side retainer member 130, best shown in Figs. 1 and 3. The retainer member 130 is adapted to fit over and enclose the forward end of the magazine channel and is connected to the block side wall 62 by threaded bolts 132.

As best shown in Figs. 15 and 18, the inner side of the retainer member 130 (namely the side facing the block side wall 62) is recessed to receive the forward end of the magazine channel and also to provide a compartment 134 having a cylindrical projection 136 upon which is rotatably mounted a take-up drum or reel 138-, which is tensioned (counterclockwise in Fig. 18) by a spiral spring 140 having its inner end fastened to the projection 136,

as at 142, and having its outer end fastened to the dru 138, as at 143. V

A flexible tape or drum 138, as at 146, and, after being wrapped around the drum, projects rearwardly from the compartment 134 and has its other end connected, as at 148, to a follower shoe 150 which is slidably mounted within the upper enclosed portion of the nail magazine 34, as shown in Figs. 1, 2 and 18. The follower shoe 150 is positioned behind the rearmost nail in the magazine and has a front shoulder 152 which bears against the shank and head of said rearmost nail. Because of the pull exerted by the spring-tensioned take-up drum 138 through the tape or wire 144, the shoe 150 exerts forward pressure on the rearmost nail, and this pressure is transmitted to the entire series of nails, by reason of the fact that the heads and shanks of successive nails are in contact with each other, as shown in Fig. 18. The follower shoe 150 is provided with a depending finger grip 153 which permits the shoe to be removed, through the open rear end of the magazine 34, to permit the magazine to be reloaded with nails when emptied.

The handle 36 has its forward end fastened to the upper end of the block side wall 62 by threaded bolts 154, as shown in Figs. 1 and 3, and extends arcuately, rearwardly and downwardly; its rear end being fastened to the nail magazine 34 by screws 156 as shown in Fig. 2. A leg member 158 extends downward from the rear end of the handle, around and beneath the magazine 34, to the level of the bottom wall 50 of the block 30. This serves to support the device, with the magazine in horizontal position, as shown in Fig. 1.

The retainer member 138 is provided with a kerf 160 extending horizontally across its front wall 162 in alignment with the keri 58 in the front wall 52 of the block 30, as shown in Fig. 3. When the retainer member is fastened to the side wall 62 of the block 30 as described above,the kerfs 58 and 130 form a continuous groove or channel within which the slide 38 is free to move horizontally and transversely of the front walls 52 and 162, as indicated in Figs. 4, 6, 7 and 8.

The retainer member 130 is also provided with a small opening 164 extending horizontally and transversely from the side wall adjoining the block wall 62. As shown in Figs. 4, 6 and 18, the opening 164 is located somewhat rearward of the front wall 162 and slightly above the bottom wall 166 of the retainer member 130, and is in communicating alignment with the compartment 60 in the block 30. A helical compression spring 168 has one end seated against the back wall 170 of the opening 164 and protrdues from said opening into the compartment 60. The other end of the spring 168 carries a supporting head 172 which bears against a pin 174 protruding downward from the bottom wall 122 of the slide 38 and into the compartment 60. It can be seen from Figs. 4 and 6 that the spring 168 urges the slide 38 transversely of the block 30 (toward the right in Figs. 4, 6, 7 and 8) and that the ram-actuated movement of the cam member 94 moves the slide 38 oppositely (toward the left in Figs. 4, 6, 7 and 8) against the pressure of the spring.

A front cover plate 176 fits over the front walls 52 and 162 and is removably fastened to said walls by a plurality of threaded bolts 178, as illustrated in Figs. 1, 2 and 3. The plate serves to keep the slide 38 and the pins 66 and 67 in place, in addition to protecting the operating mechanism from dust and dirt.

The operation of the above-described embodiment is as follows, starting with the position of Figs. 4 and 5 in which there is no nail between the jaw members 40 and 42, the ram 32 is held in elevated position by the spring 88, the slide 38 is held in right-shifted position by the spring 168, and the frontmost nail in the magazine 34 is urged forwardly so that part of its head protrudes into the end portion of the top groove 114 in the back wall 112 of the slide.

wire 144 has one end fastened to the.

The ram 32 is driven down by a blow or pressure upon its knob 86 until the cam member 94 contacts the cam follower surface 106 and then shifts the slide laterally, against the pressure of the spring 168, to the position shown in Figs. 6, 7 and 9, wherein the vertical groove or notch 120 is opposite the forward end of the magazine 34. In this position, the frontmost nail, under the pressure of the spring-urged follower shoe 150, pops out slightly with its shank fitting within the vertical groove 120 and its head protruding slightly further beyond the back groove 114 and into the communicating portion of the front groove 108 as shown in Fig. 9. As shown in Figs. 7 and 9, the main cylindrical portion of the ram 32, in this position, has moved between the two jaw members 40 and 42 and has spread apart their faces 78 and and also their nail-receiving fingers 82 and 84.

When the ram 32 is released, it moves back upward to its original position, under the pressure of its spring 88. When the cam member 94 is raised out of the cam-receiving notch 102, the slide is moved laterally (toward the right in Figs. 8 and 10) by the spring 168 and carries with it the frontmost nail (which has its shank disposed within the vertical groove as described above) until said nail reaches the position shown in Figs. 8 and 10.

In this last-mentioned position, the shank of the nail is intercepted by the longer frontmost finger 84 of the jaw member 42; further spring-actuated movement of the slide producing a' camming action enabling the finger to pry the nail shank out of the slide grooves (lateral force being exerted against the nail head by the trailing edge of the groove 108), so that the nail moves between the opposed fingers 82 and 84 to' a centered position intermediate the jaw faces 78 and 80; the nail being held in this centered position by the opposed pressure of the jaw members.

At this point, it should be noted that the nailing ma chine of the present invention can be used equally well in inverted or otherwise inclined position; the face 92 of the ram 32 preventing the nail from falling out of its jaw-gripped position when the machine is turned upside down.

After the nail has been pried loose, the spring-actuated lateral movement of the slide 38 continues beyond the position of Figs. 8 and 10 to the position shown in Figs. 11 and 12. As indicated in Figs. 10 and 11, as soon as the first nail has been shifted laterally from the magazine, the next nail pops out into the groove'114.

Upon the next downward movement of the ram 32, its striking face 92 contacts the head of the nail held by the jaws and forces it free of said jaws (which are spread apart by entry therebetween of the main cylindrical portion of the ram as noted above), driving it downward to the embedding position shown in Fig. 13. During this second downward movement of the ram 32, the slide 38 has again been shifted from the position of Figs. 4 and 5 to the position of Figs. 6, 7 and 9, permitting the second nail to be seated within the vertical groove 120, in the manner described above. When the ram is released, the slide moves under spring-pressure to the position of Figs 11 and 12 (after passing the position of Figs. 8 and 10), so as to position the second nail between the jaw members.

Upon each subsequent downward movement of the ram 32, the nail previously positioned between the jaw members is driven home into the work piece upon which the open bottom of the elliptical chamber 48 rest-s, while on the upward return movement of the ram the next nail is automatically positioned between the jaw members.

It can be seen, therefore, that the operator holds the handle 36 with one hand and operates theram with the other hand and is able to drive nails just as fast as he can depress the ram.

Since the device weighs only a few pounds, it can be handled conveniently and can be shifted easily along any work surface to facilitate the driving home of nails in rapid succession.

The magazine hammer is especially Well suited for the roofing art, in the installation of shingles, etc. However, it can also be used in any environment wherein rapid nailing is required, including, but not limited to, the installation of flooring, siding, fencing, etc.

It is apparent that the extra width of the spaced shoulders 128 of the nail magazine 34 will accommodate nails of different head diameter, while the tapered concave faces 73 and 80 of the jaw members 49 and 42 accomplish the same result. That is, a nail with a larger head diameter would be held between the jaw members at a level slightly above that shown in Fig. 11, while a nail with a smaller head diameter would be held at a slightly lower level. There is ample clearance between the magazine flanges 124 and 126 and between the lower ends of the jaw member-s 40 and 42 to accommodate nail shanks of difiFerent diameter. Since the bottom of the magazine is open, as is also the case with the lower ends of the jaw members, it can be seen that the length of the nail shank is immaterial and that such length can vary through relatively wide limits without necessitating any change in the construction or proportions of the dev1ce.

The present invention may be embodied in other specific forms and, therefore, the above-described embodiment is to be considered in all respects merely as illustrative and not restrictive; reference being made to the appended claims as indicating the true scope of this invention.

Having thus described my invention, I claim as new and desire to protect by Letters Patent the following:

1. In a nailing machine, a block having a vertical opening extending downward from its top and having an enlarged communicating chamber extending upward from its bottom, a pair of opposed nail-gripping jaws pivotally mounted within said chamber, a ram slidably mounted within said vertical opening and protruding upward therefrom beyond said block, said ram having a lowermost horizontal driving face and being normally spring-tensioned to uppermost position wherein it is elevated above said chamber, said ram being movable downwardly against its normal spring tension so that its lower portion passes between said jaws to nail-driving position, a magazine for holding a plurality of nails or the like in successive head-supported abutting relationship, springtensioned follower means bearing against the last nail in the magazine and urging the nails toward the dispensing end of said magazine, a slide movably mounted upon said block and constructed and arranged to reciprocate intermediate the dispensing end of the magazine and the block chamber, one wall of said slide being grooved to receive the shank and the head of the first nail in the magazine when said slide is shifted in one direction, means disposed within the block chamber for removing the nail from the slide and for transferring it to the opposed jaws when said slide is shifted in the other direction, means carried by the ram contacting the slide whereby downward movement of the ram causes shifting of the slide to nail-receiving position, and means for shifting said slide oppositely to feed the nail to the jaws during upward return movement of said ram.

2. A construction according to claim 1 wherein a slide-actuating cam member is slidably mounted on the block for vertical reciprocation with the ram and has a downwardly-directed inclined camming edge, and wherein a cam-receiving notch is provided on the slide, said notch having an inclined cam-follower surface adapted to be contacted by the camming edge of the downwardly moving earn member,-thereby to translate the downward movement into a generally horizontal lateral movement of the slide.

3. A construction according to claim 2 wherein the slide is moved to nail-receiving position by the cam mem- Cit her, and wherein spring-means are provided for returning the slide to jaw-feeding position upon upward movement of the ram and the cam member.

4. A construction according to claim 3 wherein the opposed nail-gripping jaws are provided with adjoining finger portions both extending generally horizontally in the same lateral direction, one of said finger portions being constructed and arranged to intercept the shank of the nail in the slide and to pry the nail loose from the slide during the jaw-feeding movement of the slide, said adjoining finger portions thereafter operating to guide the aforesaid removed nail into position between the jaws.

5. A construction according to claim 4 wherein each of the jaws is integrally formed of resilient metal or the like, the upper end of each jaw being bent to provide a pin-encircling sleeve terminating in a laterally extending spring shoulder, said shoulders bearing against adjacent surfaces so as to urge the main depending portions of the jaws toward each other.

6. A construction according to claim 5 wherein the ram has a lower portion and an upper enlarged portion provided with a bottom shoulder, said shoulder being constructed and arranged to contact and spread the jaws when said ram is moved downward to nail-driving position.

7. A construction according to claim 4 wherein the jaws have opposed gripping faces which are concavely arcuate in cross-section and which are vertically elongated and taper downwardly and inwardly to provide vertically variable nail-head clearance.

8. In a nailing machine, a generally vertically disposed block having a vertical opening extending downward from the top thereof and having a vertical chamber of enlarged cross-section extending upward from its bottom and communicating with the lower end of the first-mentioned opening, a ram slidably mounted within the firstmentioned opening and protruding upward therefrom beyond the top of the block, spring means tensioning said ram to uppermost position, a pair of opposed verti cally elongated nail-holding jaws pivotally mounted, in depending relationship, within said chamber in position such that the ram, when depressed, will pass therebetween and will spread the jaws apart, a magazine channel member for holding a plurality of nails in successive head-supported abutting relationship, said channel member having its dispensing end mounted on the side of the block, the upper portion of the channel member providing a pair of elongated spaced shoulders for supporting the nail heads, a spring-tensioned follower disposed within the upper portion of the channel member and bearing against the last nail so as to urge all of the nails toward the dispensing end of the magazine, a slide horizontally movable with respect to the block, said slide being disposed within a kerf formed within the front face of the block, said slide being constructed and arranged to reciprocate horizontally between the magazine channel member and the block chamber, both said channel member'and said chamber opening to the same Wall of said slide, said slide wall being grooved horizontally and vertically to receive the head and shank of the first nail in the magazine channel member, when said slide is shifted in one direction, means disposed within the block chamber for removing the nail from the grooved slide wall when the slide is shifted in the other direction and for transferring the nail to the jaws, connecting means for shifting the slide during downward movement of the ram, and means for oppositely shifting the slide during upward movement of the ram.

9. A construction according to claim 8 wherein a slideactuator cam member is movably mounted on the front face of the block and is connected to the ram through a vertical slot in the block, said cam member having a downwardly-directed inclined camming edge, and wherein the slide is provided with a cam-receiving notch having an inclined cam-follower surface adapted to be con- 9 tacted by said camming edge during downward movement of the cam member so as to produce a transverse horizontal movement of the slide to nail-receiving position.

10. A construction according to claim 9 wherein the cam-receiving notch is disposed on the slide wall opposite that containing the nail-receiving slot.

11. A construction according to claim 9 wherein the slide is moved to nail-receiving position by the cam member, and wherein spring-means are provided for returning the slide to jaw-feeding position upon upward movement of the ram and the cam member.

12. A construction according to claim 8 wherein the opposed nail-gripping jaws are provided with adjoining finger portions both extending generally horizontally in the same lateral direction, one of said finger portions being constructed and arranged to intercept the shank of the nail in the slide and to pry the nail loose from the slide during the jaw-feeding movement of the slide, said adjoining finger portions thereafter operating to guide the aforesaid removed nail into position between the aws.

13. A construction according to claim 12 wherein each of the jaws is integrally formed of resilient metal or the like, the upper end of each jaw being bent to provide 10 a pin-encircling sleeve terminating in a laterally extending spring shoulder, the shoulders bearing against adjoining surfaces so as to urge the main depending portions of the jaws toward each other.

14. A construction according to claim 13 wherein the ram has a lower portion and an upper enlarged portion provided with a bottom shoulder, said shoulder being constructed and arranged to contact and spread the jaws when said ram is moved downward to nail-driving position.

15. A construction according to claim 12 wherein the jaws have opposed gripping faces which are concavely arcuate in cross-section and which are vertically elongated and taper downwardly and inwardly to provide vertically varying nail-head clearance.

References Cited in the file of this patent UNITED STATES PATENTS 583,674 Eaton June 1, 1897 2,058,034 Prochiette Oct. 20, 1936 2,169,433 Roy Aug. 15, 1939 2,237,458 Thayer Apr. 8, 1941 2,430,321 Anstett Nov. 4, 1947 2,734,192 True Feb. 14, 1956 

